1. Field of the Invention
The present invention relates to an image reading system for easily obtaining a desired final image by preliminarily displaying an image read by an image reading device under various image reading conditions, and obtaining a final image after determining final reading conditions by referring to the preliminary image read under the various reading conditions. The present invention also relates to an image reading apparatus to read the images according to a reading condition, and a memory medium to store control procedures for reading the image.
2. Description of the Related Art
A film scanner is a known type of image reading apparatus for reading an image photographed by a camera and reproduced on film. The film scanner reads an image on the film negative, or reversal film, in accordance with instructions from a host computer serving as a control device, and outputs the image read from the film negative to the host computer. The host computer displays a frame image of the film on a monitor screen.
An image reading system normally comprises an image reading apparatus and a host computer. Further, it is known to configure the image reading apparatus and the host computer in a single enclosure. A conventional image reading apparatus includes a line sensor to read an image, and employs either a penetration method to provide the line sensor with light penetrated through the film document, or a reflection method to provide the line sensor with light reflected from the film document. Further, it is also well known that, in terms of the positional relationship between the line sensor and the film document, the film document may be moved with respect to the line sensor, or otherwise.
The conventional line sensor includes an image accumulation section consisting of multiple photoelectric conversion sections arranged in a row, and a transfer section to transfer electric charge accumulated in each image accumulation section. To read information, the line sensor starts scanning sequentially in a lengthwise direction from one end to the other end, and sends the information thus read externally by transferring the electrical charge accumulated in each image accumulation section to the transfer section. An image reading scan is referred to as a main scanning and the direction of the image reading scan is referred to as the main scanning direction. A two-dimensional image in an image memory area of the film is read by moving the film document and line sensor relative to each other in a secondary scanning direction crossing the main scanning direction.
With a conventional image reading system, a final output image is obtained by performing the following steps. Initially, an image read under certain conditions is displayed preliminarily on the monitor screen. Next, a user conceptualizes, in his/her own mind, a final image that he/she would like to achieve by viewing the preliminarily displayed image. After conceptualizing a final image, the user enters modified reading conditions with modified gradation characteristics and color balance. Then, the final output image is read under the modified reading conditions. At this time, the final output image, which is obtained under the above-described modified reading conditions, is simulated for the display through image processing to provide convenience for the user.
However, since the conventional image reading system, requires the user to conceptualize the final image to be achieved to set the reading conditions, the image simulated based on the set conditions often has unsatisfactory results. In that case, it is necessary to search the reading conditions for an image the user wants to ultimately achieve by repeatedly setting the reading conditions and displaying the simulated images until a satisfactory result is obtained. Therefore, the image reading process with the conventional image reading system involves very complicated reading operations if the above-described procedures must be repeated more than once.